The single equivalent moving dipole model does not require spatial anatomical information to determine cardiac sources of activation.
The single equivalent moving dipole model does not require spatial anatomical information to determine cardiac sources of activation.
复制标题
单一等效移动偶极子模型不需要空间解剖信息来确定心脏激活源。
DOI：
10.1109/jbhi.2013.2268012
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发表时间：
2014
影响因子：
7.7
通讯作者：
Armoundas,AntonisA
中科院分区：
文献类型：
--
作者：
Sohn,Kwanghyun;Lv,Wener;Lee,Kichang;Galea,AnnaM;Hirschman,GordonB;Hayward,AlisonM;Cohen,RichardJ;Armoundas,AntonisA
射频导管消融（RCA）是一种治疗室性心动过速（VT）的方法。RCA程序的一个关键特征是需要一种便于识别目标消融部位的测绘方法。在这项研究中，我们研究了参考电位的位置和空间解剖约束对确定VT消融治疗靶点的算法准确性的影响。该算法涉及使用嵌入在无限均匀体积导体中的单个等效移动偶极子（SEMD）模型处理体表电位来模拟心脏电活动。我们采用猪动物模型和一个由9个电极组成的电极阵列，这些电极被缝合在右心室的心外膜表面。我们确定了两个电位参考电极位置：离心脏最远的电极（R1）和所有64个体表电极电位的平均值（R2）。此外，我们还开发了用于获取SEMD位置的算法的三种空间“约束”方案：一种不对逆解施加任何约束（S1），一种将解约束为与心脏对应的体积（S2），一种将解约束为与体表对应的体积（S3）。我们发现R2S1是定位体内已知位置心外膜电源最准确的方法（p < 0.05，与R1S1在最早激活时间eat相比）。尽管均匀体积导体在偶极子位置估计值中引入了与真实偶极子位置相比的系统误差，但我们观察到，R1S1和R2S1组合的电极间距离估计值与真实位置相比的总体误差分别为0.4±0.4 cm和0.4±0.1 cm，在EAT （p = N.S.）和1.0±0.6 cm和0.5±0.4 cm，在起搏器峰值时间（PST,）。总之，我们从体表电位估计SEMD参数的算法可能是一种有用的方法，可以在RCA过程中快速准确地将导管尖端引导到目标部位，而不需要传统成像方式获得的空间解剖信息。
Radio-frequency catheter ablation (RCA) is an established treatment for ventricular tachycardia (VT). A key feature of the RCA procedure is the need for a mapping approach that facilitates the identification of the target ablation site. In this study, we investigate the effect of the location of the reference potential and spatial anatomical constraints on the accuracy of an algorithm to identify the target site for ablation therapy of VT. This algorithm involves processing body surface potentials using the single equivalent moving dipole (SEMD) model embedded in an infinite homogeneous volume conductor to model cardiac electrical activity. We employed a swine animal model and an electrode array of nine electrodes that was sutured on the epicardial surface of the right ventricle. We identified two potential reference electrode locations: at an electrode most far away from the heart (R1) and at the average of all 64 body surface electrode potentials (R2). Also, we developed three spatial “constraining” schemes of the algorithm used to obtain the SEMD location: one that does not impose any constraint on the inverse solution (S1), one that constrains the solution into a volume that corresponds to the heart (S2), and one that constrains the solution into a volume that corresponds to the body surface (S3). We have found that R2S1 is the most accurate approach (p <; 0.05 versus R1S1 at earliest activation time-EAT) for localizing epicardial electrical sources of known locations in vivo. Although the homogeneous volume conductor introduces systematic error in the estimated compared to the true dipole location, we have observed that the overall error of the estimated interelectrode distance compared to the true one was 0.4 ± 0.4 cm and 0.4 ± 0.1 cm for the R1S1 and R2S1 combinations, respectively, at the EAT (p = N.S.) and 1.0 ± 0.6 and 0.5 ± 0.4 cm, respectively, at the pacing spike time (PST, ). In conclusion, our algorithm to estimate the SEMD parameters from body surface potentials can potentially be a useful method to rapidly and accurately guide the catheter tip to the target site during a RCA procedure without the need for spatial anatomical information obtained by conventional imaging modalities.